Conjugated linoleic acid supplementation for 1 y reduces body fat mass in healthy overweight humans

BACKGROUND: Short-term trials showed that conjugated linoleic acid (CLA) may reduce body fat mass (BFM) and increase lean body mass (LBM), but the long-term effect of CLA was not examined. OBJECTIVE: The objective of the study was to ascertain the 1-y effect of CLA on body composition and safety in healthy overweight adults consuming an ad libitum diet. DESIGN: Male and female volunteers (n = 180) with body mass indexes (in kg/m(2)) of 25-30 were included in a double-blind, placebo-controlled study. Subjects were randomly assigned to 3 groups: CLA-free fatty acid (FFA), CLA-triacylglycerol, or placebo (olive oil). Change in BFM, as measured by dual-energy X-ray absorptiometry, was the primary outcome. Secondary outcomes included the effects of CLA on LBM, adverse events, and safety variables. RESULTS: Mean (+/- SD) BFM in the CLA-triacylglycerol and CLA-FFA groups was 8.7 +/- 9.1% and 6.9 +/- 9.1%, respectively, lower than that in the placebo group (P < 0.001). Subjects receiving CLA-FFA had 1.8 +/- 4.3% greater LBM than did subjects receiving placebo (P = 0.002). These changes were not associated with diet or exercise. LDL increased in the CLA-FFA group (P = 0.008), HDL decreased in the CLA-triacylglycerol group (P = 0.003), and lipoprotein(a) increased in both CLA groups (P < 0.001) compared with month 0. Fasting blood glucose concentrations remained unchanged in all 3 groups. Glycated hemoglobin rose in all groups from month 0 concentrations, but there was no significant difference between groups. Adverse events did not differ significantly between groups. CONCLUSION: Long-term supplementation with CLA-FFA or CLA-triacylglycerol reduces BFM in healthy overweight adults.     

Supplementation with conjugated linoleic acid for 24 months is well tolerated by and reduces body fat mass in healthy, overweight humans

After 12 mo in a randomized, double-blind, placebo-controlled trial of conjugated linoleic acid (CLA) supplementation (2 groups received CLA as part of a triglyceride or as the free fatty acid, and 1 group received olive oil as placebo), 134 of the 157 participants who concluded the study were included in an open study for another 12 mo. The goals of the extension study were to evaluate the safety [with clinical chemistry analyses and reported adverse events (AEs)] and assess the effects of CLA on body composition [body fat mass (BFM), lean body mass (LBM), bone mineral mass (BMM)], body weight, and BMI. All subjects were supplemented with 3.4g CLA/d in the triglyceride form. Circulating lipoprotein(a) and thrombocytes increased in all groups. There was no change in fasting blood glucose. Aspartate amino transferase, but not alanine amino transferase, increased significantly. Plasma total cholesterol and LDL cholesterol were reduced, whereas HDL cholesterol and triglycerides were unchanged. The AE rate decreased compared with the first 12 mo of the study. Body weight and BFM were reduced in the subjects administered the placebo during the initial 12 mo study (-1.6 +/- 3.2 and -1.7 +/- 2.8 kg, respectively). No fat or body weight changes occurred in the 2 groups given CLA during the initial 12 mo. LBM and BMM were not affected in any of the groups. Changes in body composition were not related to diet and/or training. In conclusion, this study shows that CLA supplementation for 24 mo in healthy, overweight adults was well tolerated. It confirms also that CLA decreases BFM in overweight humans, and may help maintain initial reductions in BFM and weight in the long term.     

Conjugated linoleic acid reduces body fat mass in overweight and obese humans

Conjugated linoleic acid (CLA) has been shown to reduce body fat mass (BFM) in animals. To investigate the dose-response relationships of conjugated linoleic acid with regard to BFM in humans, a randomized, double-blind study including 60 overweight or obese volunteers (body mass index 25-35 kg/m(2)) was performed. The subjects were divided into five groups receiving placebo (9 g olive oil), 1.7, 3.4, 5.1 or 6.8 g conjugated linoleic acid per day for 12 wk, respectively. Dual-energy X-ray absorptiometry was used to measure body composition [measurements at wk 0 (baseline), 6 and 12]. Of the 60 subjects, 47 completed the study. Eight subjects withdrew from the study due to adverse events; however, no differences among treatment groups were found regarding adverse events. Repeated-measures analysis showed that a significantly higher reduction in BFM was found in the conjugated linoleic acid groups compared with the placebo group (P: = 0.03). The reduction of body fat within the groups was significant for the 3.4 and 6.8 g CLA groups (P: = 0.05 and P: = 0.02, respectively). No significant differences among the groups were observed in lean body mass, body mass index, blood safety variables or blood lipids. The data suggest that conjugated linoleic acid may reduce BFM in humans and that no additional effect on BFM is achieved with doses > 3.4 g CLA/d.     

Effects of milk supplementation with conjugated linoleic acid (isomers cis-9, trans-11 and trans-10, cis-12) on body composition and metabolic syndrome components

The effects of conjugated linoleic acid (CLA) on body weight and body composition in man are controversial. The aim of this study was to investigate the effects of milk supplementation with CLA on body composition and on the biochemical parameters of the metabolic syndrome. This was a randomised, double-blind, placebo-controlled trial. Subjects were randomised to a daily intake of 500 ml milk supplemented with 3 g CLA (using a mixture of the bioactive isomers cis-9, trans-11 and trans-10, cis-12, marketed as Tonalin, Naturlinea; Central Lechera Asturiana) or placebo for 12 weeks. Sixty healthy men and women (aged 35-65 years) with signs of the metabolic syndrome participated (BMI 25-35 kg/m2). Dual-energy X-ray absorptiometry was used to measure body composition (week 0 baseline and week 12). Total fat mass in the CLA-milk subgroup with a BMI < or = 30 kg/m2 decreased significantly while no changes were detected in the placebo group (approximately 2 %, P = 0.01). Trunk fat mass showed a trend towards reduction (approximately 3 %, P = 0.05). CLA supplementation had no significant effect on the parameters of the metabolic syndrome, nor was it associated with changes in haematological parameters or renal function. The supplementation of milk with 3 g CLA over 12 weeks results in a significant reduction of fat mass in overweight but not in obese subjects. CLA supplementation was not associated with any adverse effects or biological changes.     

Effect of conjugated linoleic acid supplementation on weight loss and body fat composition in a Chinese population

ObjectiveConjugated linoleic acid (CLA) has several benefits, including body fat reduction, as proved in animals. However, the results of CLA-induced body composition alterations in humans are inconsistent, and no related data are available for Chinese populations. This study aimed to determine whether CLA affects body weight (BW) loss and body composition of overweight and obese Chinese subjects.MethodsIn this randomized, double-blind, placebo-controlled trial, subjects with a body mass index (BMI) of 24 to 35 kg/m² randomly received 1.7 g of cis-9,trans-11 and trans-10,cis-12 CLA (n = 30) or placebo (salad oil; n = 33) in 200 mL of sterilized milk twice daily for 12 wk. Changes in body composition were determined by bioimpedance measurements.ResultsSixty-three subjects completed the study (CLA, n = 30). After 12 wk, compared with the baseline, the BW, BMI, total fat mass, fat percentage, subcutaneous fat mass, and waist-to-hip ratio decreased in the CLA group (P < 0.05). The CLA group was stratified by BMI and gender. The BW, BMI, subcutaneous fat mass, and waist-to-hip ratio decreased in 27 subjects with a BMI ≥ 27, and these indices, except subcutaneous fat mass, were lower in female subjects. The levels of total cholesterol, triacylglycerol, low-density lipoprotein, and plasma fasting glucose increased, whereas those of high-density lipoprotein decreased after 3 mo of CLA treatment. The changes were not significantly different from the baseline values.ConclusionThe supplementation of CLA for 12 wk in overweight and grade I obese Chinese subjects yielded lower obesity indices, with no obvious adverse effects.     

Conjugated linoleic acid supplementation for 1 y does not prevent weight or body fat regain

BACKGROUND: Conjugated linoleic acid (CLA) is marketed as a safe, simple, and effective dietary supplement to promote the loss of body fat and weight. However, most previous studies have been of short duration and inconclusive, and some recent studies have questioned the safety of long-term supplementation with CLA. OBJECTIVE: Our aim was to assess the effect of 1-y supplementation with CLA (3.4 g/d) on body weight and body fat regain in moderately obese people. DESIGN: One hundred twenty-two obese healthy subjects with a body mass index (in kg/m2) > 28 underwent an 8-wk dietary run-in with energy restriction (3300-4200 kJ/d). One hundred one subjects who lost >8% of their initial body weight were subsequently randomly assigned to a 1-y double-blind CLA (3.4 g/d; n = 51) or placebo (olive oil; n = 50) supplementation regime in combination with a modest hypocaloric diet of -1250 kJ/d. The effects of treatment on body composition and safety were assessed with the use of dual-energy X-ray absorptiometry and with blood samples and the incidence of adverse events, respectively. RESULTS: After 1 y, no significant difference in body weight or body fat regain was observed between the treatments. The CLA group (n = 40) regained a mean (+/-SD) 4.0 +/- 5.6 kg body weight and 2.1 +/- 5.0 kg fat mass compared with a regain of 4.0 +/- 5.0 kg body weight and 2.7 +/- 4.9 kg fat mass in the placebo group (n = 43). No significant differences in reported adverse effects or indexes of insulin resistance were observed, but a significant increase in the number of leukocytes was observed with CLA supplementation. CONCLUSION: A 3.4-g daily CLA supplementation for 1 y does not prevent weight or fat mass regain in a healthy obese population.     

Cognitive behavioral therapy improves diet and body composition in overweight and obese adolescents

BACKGROUND: Cognitive behavioral therapy (CBT) teaches behavioral and cognitive strategies that focus on achieving and maintaining lifestyle changes. OBJECTIVE: We examined the effectiveness of a CBT program (CHOOSE HEALTH) for improving body composition, diet, and physical activity in overweight and obese adolescents. DESIGN: Adolescents [16 male, 31 female; aged 14.5 +/- 1.6 y; body mass index (BMI; in kg/m(2)) 30.9 +/- 4.2] were block-matched into 2 groups by age, sex, Tanner stage, BMI, and hip and waist circumferences and were randomly assigned to CBT or no treatment (control). CBT consisted of 10 weekly sessions, followed by 5 fortnightly telephone sessions. RESULTS: Compared with the control, over 20 wk, CBT improved (significant group x time interactions) BMI (CBT, -1.3 +/- 0.4; control, 0.3 +/- 0.3; P = 0.007), weight (CBT, -1.9 +/- 1.0 kg; control, 3.8 +/- 0.9 kg; P = 0.001), body fat (CBT, -1.5 +/- 0.9 kg; control, 2.3 +/- 1.0 kg; P = 0.001), and abdominal fat (CBT, -124.0 +/- 46.9 g; control, 50.1 +/- 53.5 g; P = 0.008). CBT showed a greater reduction in intake of sugared soft drinks as a percentage of total energy (CBT, -4.0 +/- 0.9%; control, -0.3 +/- 0.9%; P = 0.005 for group x time interaction), which was related to reductions in weight (r = 0.48, P = 0.04), BMI (r = 0.53, P = 0.02), and waist circumference (r = 0.54, P = 0.02). Physical activity did not change significantly. CONCLUSIONS: A 10-wk CBT program followed by 10 wk of fortnightly phone contact improved body composition in overweight and obese adolescents. Changes in soft drink consumption may have contributed to this benefit.     

Efficacy of conjugated linoleic acid for reducing fat mass: a meta-analysis in humans

BACKGROUND: Conjugated linoleic acid (CLA) has been shown to be an effective supplement for reducing fat mass in animals, whereas results in humans have been inconsistent. OBJECTIVE: This is a meta-analysis of human studies in which CLA was provided as a dietary supplement to test its efficacy in reducing fat mass. DESIGN: We searched the PubMed database (National Library of Medicine, Bethesda, MD) and references from the resulting search to identify studies in which CLA was provided to humans in randomized, double-blinded, placebo-controlled trials and in which body composition was assessed by using a validated technique. RESULTS: We identified 18 eligible studies. Of these, 3 were single-isomer studies, and results comparing CLA isomers were inconclusive. We compared the length of treatment by using studies in which a mixture of purified isomers were used and those in which purified trans-10,cis-12 isomers were used. This comparison indicated that the effect of CLA was linear for up to 6 mo and then slowly approached an asymptote at 2 y. An analysis of the dose effect indicated that fat loss compared with placebo was -0.024 kg x g CLA(-1) x wk(-1) (P=0.03). After adjustment to the median dose of 3.2 g CLA/d, CLA was effective and produced a reduction in fat mass for the CLA group alone (0.05 +/- 0.05 kg/wk; P<0.001) and for the CLA group compared with placebo (0.09 +/- 0.08 kg/wk; P<0.001) CONCLUSION: Given at a dose of 3.2 g/d, CLA produces a modest loss in body fat in humans.     

Comparison between bioelectrical impedance analysis and body mass index methods in determination of obesity prevalence in Ahvazi women

BACKGROUND: Obesity has an increasing trend worldwide. Recently, application of body mass index (BMI) cutoff points of obesity classification for all population studies has been questioned. On the other hand, bioelectrical impedance analysis (BIA) is a safe, accurate, reliable and inexpensive method for screening the overweight and obesity in such studies. OBJECTIVES: There were three objectives followed in this research: to determine the prevalence of obesity and overweight in married women using BMI and BIA methods; to evaluate the correlation between these methods; and to compare the women's obesity degrees according to their educational levels. METHOD: Six hundred and thirty-seven healthy married women 18-40 years aged, who had referred to 14 health centers of the city of Ahvaz (center of Khouzestan province, south-west of Iran) were recruited in a cross-sectional design, and their socio-economic and anthropometric questionnaires were completed by the trained students. Body fat percent (%BF) and body fat mass (BFM) were measured using BIA method. BMI>25 and >30 kg/m(2) were used as criteria for determining the overweight and obese women, respectively. %BF>35% was regarded as cutoff for defining obesity. RESULTS: Mean age+/-s.d. of the women was 26.9+/-5.8 years and majority of them were housewives with secondary educational level. Their BMI, %BF, waist-to-hip ratio, and mid-upper arm circumference means were: 25.9(4.7) kg/m(2), 27.6(7.3)%, 0.75(0.08) and 27.9(3.9) cm, respectively. Central obesity was prevalent in 21.2% of the subjects.Prevalence of obesity determined by BMI and BIA methods was 18.3 and 15.5% and women within normal ranges were detected in 44.7 and 46% of the subjects by these methods, respectively. However, thin (underweight) women were 2.6 and 14.6% of the subjects studied, respectively. About one half of the women were overweight or obese. BMI was statistically correlated with BFM (r=0.86; P<0.0001) and %BF (r=0.77; P<0.0001). Women with higher educational levels had lower body fat percentage and BMI than the other subjects with lower degrees (P<0.05). CONCLUSION: Obesity and overweight is prevalent in about one-half of the Ahvazian married women and more than one-fifth of the subjects have central obesity. BIA and BMI methods can similarly detect the normal and obese married women but they are different in determining the underweight female subjects. Women with higher educational grades tend to have lower BMI levels.     

Effects of soya isoflavones and exercise on body composition and clinical risk factors of cardiovascular diseases in overweight postmenopausal women: a 6-month double-blind controlled trial

Results from a pilot project indicate that isoflavones and exercise could have an additive effect on body composition and clinical risk factors of CVD in postmenopausal women. The objective of the present study was to assess the combined effect of exercise and isoflavones in overweight-to-obese postmenopausal women. In this double-blind randomised controlled trial, 100 overweight-to-obese (BMI 29·9 (sd 3·2)?kg/m2) postmenopausal women were assigned to four groups: (1) placebo (PLA); (2) isoflavones (ISO); (3) exercise and placebo (Ex+PLA); (4) exercise and isoflavones (Ex+ISO). The supplementation contained 70?mg/d of isoflavones. Exercise consisted of three weekly sessions of resistance training and aerobics. Outcome measures included fat mass (FM), lean body mass (LBM), bone mineral density, lipid profile, fasting glucose, fasting insulin and insulin resistance (homeostasis assessment model). The main effects of exercise were observed for total FM (P?=?0·02), FM% (P?相似文献   

Effects of two conjugated linoleic Acid isomers on body fat mass in overweight humans

OBJECTIVE: To examine the effects of two different conjugated linoleic acid (CLA) isomers at two different intakes on body composition in overweight humans. RESEARCH METHODS AND PROCEDURES: Eighty-one middle-aged, overweight, healthy men and women participated in this bicentric, placebo-controlled, double-blind, randomized study. For 6 weeks (run-in period), all subjects consumed daily a drinkable dairy product containing 3 g of high oleic acid sunflower oil. Volunteers were then randomized over five groups receiving daily either 3 g of high oleic acid sunflower oil, 1.5 g of cis-9,trans-11 (c9t11) CLA, 3 g of c9t11 CLA, 1.5 g of trans-10,cis-12 (t10c12) CLA, or 3 g of t10c12 CLA administrated as triacylglycerol in a drinkable dairy product for 18 weeks. Percentage body fat mass and fat and lean body mass were assessed at the end of the run-in and experimental periods by DXA. Dietary intake was also recorded. RESULTS: Body fat mass changes averaged 0.1 +/- 0.9 kg (mean +/- SD) in the placebo group and -0.3 +/- 1.4, -0.8 +/- 2.1, 0.0 +/- 2.3, and -0.9 +/- 1.7 kg in the 1.5-g c9t11, 3-g c9t11, 1.5-g t10c12, and 3-g t10c12 groups, respectively. Changes among the groups were not significantly different (p = 0.444). Also, lean body mass and dietary intake were not significantly different among the treatments. DISCUSSION: A daily consumption of a drinkable dairy product containing up to 3 g of CLA isomers for 18 weeks had no statistically significant effect on body composition in overweight, middle-aged men and women.     

Plasma vitamin C is inversely related to body mass index and waist circumference but not to plasma adiponectin in nonsmoking adults

We examined the relationships between plasma vitamin C, adiposity, and the collagen-like adipokine, adiponectin. Of 118 sedentary, nonsmoking adults participating in the cross-sectional trial (35 men and 83 women aged 38.7 +/- 1.0 y with BMI of 30.4 +/- 0.6 kg/m2, plasma vitamin C concentrations of 43.5 +/- 1.3 micromol/L, and plasma adiponectin concentrations of 8.9 +/- 0.3 mg/L), 54% were obese and 24% were overweight. Plasma vitamin C was inversely related to BMI, percentage of body fat, and waist circumference in both women and men (r = -0.383 to -0.497, P < 0.025). In women but not men, these associations remained significant after controlling for body mass. Plasma vitamin C was directly related to plasma adiponectin in the women after controlling for age and vitamin C supplement use (r = 0.222, P = 0.049) but not after controlling for body mass. Twenty obese men and women participated in an intervention trial and consumed an energy-restricted diet low in vitamin C (approximately 38 mg/d) for 8 wk. Subjects were stratified by age, gender, and BMI and randomly assigned to receive placebo or vitamin C (500 mg) capsules daily. At baseline, plasma adiponectin was directly related to plasma vitamin C (r = 0.609, P = 0.021) and inversely related to body mass (r = -0.785, P = 0.001). Body mass decreased significantly during the 8 wk study in both the vitamin C (n = 6, -5.9 +/- 0.9 kg) and placebo groups (n = 8, -6.5 +/- 0.7 kg). Plasma adiponectin increased 13% from baseline by wk 8 in both groups (P < 0.05). In summary, plasma vitamin C was inversely related to markers of adiposity, particularly in women, but vitamin C supplementation did not influence the circulating concentration of adiponectin.     

Resting metabolic rate in severely obese diabetic and nondiabetic subjects

OBJECTIVES: To compare the resting metabolic rate (RMR) between diabetic and nondiabetic obese subjects and to develop a predictive equation of RMR for these subjects. RESEARCH METHODS AND PROCEDURES: Obese adults (1088; mean age = 44.9 +/- 12.7 years) with BMI > or = 35 kg/m2 (mean BMI = 46.4 +/- 8.4 kg/m2) were recruited. One hundred forty-two subjects (61 men, 81 women) were diagnosed with type 2 diabetes (DM), giving the prevalence of DM in this clinic population as 13.7%. RMR was measured by indirect calorimetry, and several multivariate linear regression models were performed using age, gender, weight, height, BMI, fat mass, fat mass percentage, and fat-free mass as independent variables. RESULTS: The severely obese patients with DM had consistently higher RMR after adjustment for all other variables. The best predictive equation for the severely obese was RMR = 71.767 - 2.337 x age + 257.293 x gender (women = 0 and men = 1) + 9.996 x weight (in kilograms) + 4.132 x height (in centimeters) + 145.959 x DM (nondiabetic = 0 and diabetic = 1). The age, weight, and height-adjusted least square means of RMR between diabetic and nondiabetic groups were significantly different in both genders. DISCUSSION: Severely obese patients with type 2 diabetes had higher RMR than those without diabetes. The RMR of severely obese subjects was best predicted by an equation using age, gender, weight, height, and DM as variables.     

Body composition and hormonal adaptations associated with forskolin consumption in overweight and obese men

OBJECTIVE: This study examined the effect of forskolin on body composition, testosterone, metabolic rate, and blood pressure in overweight and obese (BMI > or = 26 kg/m(2)) men. RESEARCH METHODS AND PROCEDURE: Thirty subjects (forskolin, n = 15; placebo, n = 15) were studied in a randomized, double-blind, placebo-controlled study for 12 weeks. RESULTS: Forskolin was shown to elicit favorable changes in body composition by significantly decreasing body fat percentage (BF%) and fat mass (FM) as determined by DXA compared with the placebo group (p < or = 0.05). Additionally, forskolin administration resulted in a change in bone mass for the 12-week trial compared with the placebo group (p < or = 0.05). There was a trend toward a significant increase for lean body mass in the forskolin group compared with the placebo group (p = 0.097). Serum free testosterone levels were significantly increased in the forskolin group compared with the placebo group (p < or = 0.05). The actual change in serum total testosterone concentration was not significantly different among groups, but it increased 16.77 +/- 33.77% in the forskolin group compared with a decrease of 1.08 +/- 18.35% in the placebo group. DISCUSSION: Oral ingestion of forskolin (250 mg of 10% forskolin extract twice a day) for a 12-week period was shown to favorably alter body composition while concurrently increasing bone mass and serum free testosterone levels in overweight and obese men. The results indicate that forskolin is a possible therapeutic agent for the management and treatment of obesity.     

应用4种肥胖判定计算方法及标准2825例成人对比分析

目的探讨4种肥胖判定计算方法标准的差异。方法入选2825例住院患者和门诊查体人员，男性2446例，女性379例，年龄22～81岁。测定身高和体质量。通过公式计算标准体质量、体质量指数（BMI）和体脂含量及肥胖指数（OI）。根据BMI≥25kg/m^2、BMI≥27kg/m^2、BMI≥28kg/m^2判定肥胖者例数分别为：1419例、680例和435例；超出标准体质量20％者649例；体脂含量男性〉25％、女性〉33％者639例。结果〉标准体质量20％和超过标准体脂含量判定的肥胖均与BMI≥25kg/m^2判定肥胖的比较，差异有统计学意义（P〈0．05）；〉标准体质量20％和超过标准体脂含量判定的肥胖均与BMI≥27kg/m^2判定的肥胖比较，差异无统计学意义（P〉0．05）；〉标准体质量20％和超过标准体脂含量判定的肥胖均与BMI≥28kg/m^2判定的肥胖比较，差异有统计学意义（P〈0．05）。结论BMI≥27kg／m^2判定肥胖与超重20％和亚太地区的体脂含量判定肥胖标准相符。     

Effects of equal weight loss with orlistat and placebo on body fat and serum fatty acid composition and insulin resistance in obese women

BACKGROUND: Dietary fat has been reported to influence insulin sensitivity. OBJECTIVE: The objective of the study was to determine how identical weight loss (target: loss of 8% of body weight over 3-6 mo) in women taking orlistat or placebo combined with a hypocaloric diet influences body composition and insulin sensitivity. DESIGN: Forty-seven obese women [body mass index (in kg/m(2)): 32.1 +/- 0.4] were randomly assigned to receive either orlistat (120 mg 3 times daily; n = 23) or placebo (n = 24) with a hypocaloric diet. Whole-body insulin sensitivity (insulin clamp technique), serum fatty acids, and body composition (magnetic resonance imaging) were measured before and after weight loss. RESULTS: The groups did not differ significantly at baseline with respect to age, body weight, intraabdominal and subcutaneous fat volumes, or insulin sensitivity. Weight loss did not differ significantly between the orlistat (7.3 +/- 0.2 kg, or 8.3 +/- 0.1%) and placebo (7.4 +/- 0.2 kg, or 8.2 +/- 0.1%) groups. Insulin sensitivity improved significantly (P < 0.001) and similarly after weight loss in the orlistat (from 4.0 +/- 0.3 to 5.1 +/- 0.3 mg x kg fat-free mass(-1) x min(-1)) and placebo (from 4.4 +/- 0.4 to 5.4 +/- 0.4 mg x kg fat-free mass(-1) x min(-1)) groups. Intraabdominal fat and subcutaneous fat decreased significantly in both groups, but the ratio of the 2 decreased significantly only in the orlistat group. The proportion of dihomo-gamma-linolenic acid (20:3n-6) in serum phospholipids was inversely related to insulin sensitivity both before (r = -0.48, P < 0.001) and after (r = -0.46, P < 0.001) weight loss, but it did not change significantly in either group. CONCLUSIONS: Weight loss rather than inhibition of fat absorption enhances insulin sensitivity. A decrease in fat absorption by orlistat appears to favorably influence the ratio between intraabdominal and subcutaneous fat, which suggests that exogenous fat or its composition influences fat distribution.     

不同干预方式对超重、肥胖青少年体重指数和体脂含量的影响

目的 观察不同干预方式对超重、肥胖青少年体重指数(BMI)和体脂含量的影响,以期得到合理有效的青少年减重方案.方法 选择北京市某初中67名超重、肥胖学生为研究对象,采用随机配伍法随机分为对照组(n=16)、膳食干预组(n=22)和综合干预组(膳食+运动,n=29)3组,观察干预前后BMI和体脂率的变化情况.结果 膳食干预组(P=0.000)和综合干预组(P=0.018)试验后的BMI明显低于试验前,膳食干预组BMI的降低幅度明显大于对照组(P=0.035).膳食干预组(P=0.000,P=0.013)和综合干预组(P=0.000,P=0.000)试验后的躯干和全身体脂率均明显低于试验前,综合于预组躯干和全身体脂率的降低幅度明显大于对照组(P=0.005,P=0.003).结论 膳食和综合干预都可使青少年达到减重效果,综合干预效果更佳.

Abstract：

Objective To observe the effects of different interventions on the body mass index (BMI) and body fat content in overweight and obese adolescents, with an attempt to design reasonable weight relief program.Methods Totally 67 overweight or obese adolescents from a middle school of Beijing were randomly divided into three groups: control group ( n = 16 ), diet intervention group ( n= 22), and combined interventions group ( n =29). The changes of BMI and body fat rate (BFR) were observed. Results BMI significantly decreased after interventions ( diet intervention group: P = 0. 000; combined interventions group: P = 0. 018 ); the change of BMI in diet intervention group was significantly larger than that in control group ( P = 0. 035 ). The trunk and body BFRs also significantly decreased after interventions (diet intervention group: P=0. 000, P = 0. 013; combined interventions group: P = 0. 000, P = 0. 000 ); the changes of trunk and body BFRs were significantly larger in combined interventions group than those in control group ( P = 0.005, P = 0. 003 ). Conclusion Diet intervention and combined interventions are both effective in achieving weight loss in adolescents, and combined interventions have superior effectiveness.     

Influence of distribution of lean body mass on resting metabolic rate after weight loss and weight regain: comparison of responses in white and black women

BACKGROUND: Little is known about the effect of weight change on regional lean body mass (LBM) distribution or on racial differences in resting metabolic rate (RMR). OBJECTIVE: The study compared total and regional LBM patterns in white and black women after weight loss and regain and assessed the influence of regional LBM on variances in RMR. DESIGN: Eighteen white and 22 black women who did not differ in age, weight, and height were studied 3 times: in the overweight state, after weight reduction to the normal-weight state, and after 1 y without intervention. Total and regional lean and fat masses were assessed by dual-energy X-ray absorptiometry. RESULTS: White and black women did not differ significantly in mean (+/- SD) weight loss (13.4 +/- 3.6 and 12.7 +/- 3.2 kg, respectively) and regain (6.1 +/- 5.5 and 6.4 +/- 5.4 kg, respectively). Black subjects had significantly less trunk LBM and significantly more limb LBM at each time point (P < 0.05). In both races, weight regain was associated with significant increases in limb LBM (P < 0.05) but not in trunk LBM (P = 0.21). RMR, adjusted for total LBM and fat mass, was significantly higher in white women after weight loss (P < 0.01) and regain (P < 0.01). However, no racial difference was found when RMR was adjusted for LBM distribution. CONCLUSIONS: In both races, trunk LBM decreased with weight loss and remained lower, despite significant weight regain, which potentially reflected decreased organ mass. Regional LBM distribution explained the racial difference in RMR.     

Effect of a high-protein energy-restricted diet combined with resistance training on metabolic profile in older individuals with metabolic impairments

Adequate protein intake and resistance training are effective strategies to maintain muscle mass, but the effect of their combination on metabolic profile during weight loss remains to be determined in older adults. The main objective of this study was to determine the effect of a 16-week high-protein caloric restriction combined with resistance training on chronic disease risk factors in obese older individuals with metabolic impairments. A total of 26 overweight adults aged between 60 and 75 years (BMI 32.4 ± 3.9 kg/m²) with at least 2 factors of the metabolic syndrome participated in this study and were randomized into two groups: 1) high-protein caloric restriction (HP; n= 12) and 2) high-protein caloric restriction combined with dynamic-resistance training (HP+RT; n=14). Caloric intake was reduced by 500 kcal/d in all participants and protein intake equated 25-30% of total calories (~1.4 g/kg/d). Exercise training consisted of 3 session/week of resistance training on pulley machines. Outcome measures included total and trunk fat mass (FM), total and appendicular lean body mass (LBM), fasting glucose level, lipid profile and blood pressure. Our results showed that total and trunk FM (all p<0.0001) as well as fasting glucose (p<0.0001), triglycerides (p=0.002) and total cholesterol (p=0.03) levels decreased similarly in both groups. However, total (p=0.04) and appendicular (p=0.02) LBM decreased in the HP group only. Our data show that high-protein energy restriction improves health profile of obese elderly at high risk of chronic disease but needs to be combined with resistance training to maintain LBM.     

肥胖、超重青少年通气功能与体成分关系

目的了解肥胖、超重和体重正常青少年的通气功能差异,探讨体成分对通气功能的影响.方法对研究对象测量身高、体重、腰围、臀围,采用中国肥胖问题工作组肥胖、超重筛查标准,对筛选出的肥胖(64人)、超重(56人)和对照(75人)3组青少年进行体成分和通气功能测定.结果3组青少年用力肺活量(FVC)测量值肥胖组＞超重组＞对照组,差异无统计学意义(F=25.213,P=0.000).单位体重深吸气量(IC)、单位体表面积最大通气量(MVV)均表现为对照组＞超重组＞肥胖组,差异有统计学意义(F=10.316,P=0.000;F=9.660,P=0.000).3组青少年小气道功能差异无统计学意义.肥胖、超重男生体重及瘦体重含量与通气功能呈显著正相关,肥胖男生腰围、体脂百分比与通气功能呈负相关;肥胖、超重女生体质指数(BMI)与通气功能呈负相关.结论与对照相比,肥胖、超重青少年通气功能有一定影响,小气道功能差异无统计学意义.肥胖、超重男生瘦体重对通气功能有正性作用,体脂百分比对肥胖男、女青少年通气功能有负性作用.中心性体脂分布模式对男生通气功能有负性影响.